2

This looks like it is just the auto-renewal that took place.
https://www.avast.com/faq.php?article=AVKB136

I have never bought this program from anywhere but the official site.
That means you paid through Nexway or Digital River. Those are the two companies that handle the financial transactions for avast.
as this is NOT the first time this has happened
It seems to me that you still don't understand the auto-renewal concept.
This rip off scam you two companies are running has to be stopped.
It can be a mistake or error in their software, but it sure is not a ripoff and/or a scam.